The current various proposals at the International Maritime Organisation （IMO） for the s factor （probability of surviving a given flooding） make no reference to survival time. The paper shows a direct link of the ...The current various proposals at the International Maritime Organisation （IMO） for the s factor （probability of surviving a given flooding） make no reference to survival time. The paper shows a direct link of the ＂prime＂ s factor with the time to capsize and shows how to utilise experimental data from 30-minute test runs for the s factor based on longer duration of tests. Unexpectedly, the extension of tests has a modest effect on the survival factor, and hence-modest effect on subdivision index A. Much more important is improving a deficient formulation for the required index R, as flooding cases with si = 1 have an infinite survival time.展开更多
Chronic cerebrovascular hypoperfusion is a high-risk factor for Alzheimer＇s disease（AD） as it is conducive to beta amyloid（Ab） over-production. Brainderived neurotrophic factor（BDNF） is a member of the neurotro...Chronic cerebrovascular hypoperfusion is a high-risk factor for Alzheimer＇s disease（AD） as it is conducive to beta amyloid（Ab） over-production. Brainderived neurotrophic factor（BDNF） is a member of the neurotrophin family widely expressed in the central nervous system. The structure of the rat BDNF gene is complex, consisting of eight non-coding exons（I–VIII） and one coding exon（IX）. The BDNF gene is transcribed from multiple promoters located upstream of different 50 noncoding exons to produce a heterogeneous population of BDNF m RNAs. S-adenosylmethionine（SAM） produced in the methionine cycle is the primary methyl donor and the precursor of glutathione. In this study, a cerebrovascular hypoperfusion rat model and an Ab intrahippocampal injection rat model were used to explore the expression profiles of all BDNF transcripts in the hippocampus with chronic cerebrovascular hypoperfusion or Ab injection as well as with SAM treatment. We found that the BDNF m RNAs and protein were down-regulated in the hippocampus undergoing chronic cerebrovascular hypoperfusion as well as Ab treatment, and BDNF exons IV and VI played key roles. SAM improved the low BDNF expression following these insults mainly through exons IV and VI.These results suggest that SAM plays a neuroprotective role by increasing the expression of endogenous BDNF and could be a potential target for AD therapy.展开更多
The large dynamic range and high performance of temperature and humidity profile lidar made it a popular tool for monitoring the atmospheric environment.In this study,we carried out an accurate analysis of the key com...The large dynamic range and high performance of temperature and humidity profile lidar made it a popular tool for monitoring the atmospheric environment.In this study,we carried out an accurate analysis of the key components of the lidar system,including lasers,the emitting and receiving light paths,and photodetectors.We combined the validation of simulations with experimental testing,and then the applicability indicators and necessary conditions in accordance were suggested.For the frequency stability of the laser,when the wavelength shift is less than 0.15%,the measurement accuracy of the system can be guaranteed to be less than 5%.The degree of near-field signal distortion will be significantly impacted by the size of the geometric factor’s transition zone.The introduced measurement error is less than 2%when the deviation angle of the emission axis is less than 0.1 mrad.It has been tested that selecting a low-sensitivity detector can help to improve the sensitivity of temperature detection since this channel is sensitive to the detector’s nonlinearity.To enhance lidar’s detection capabilities and direct the lidar system design process,it is beneficial to analyze the precision of the key components.展开更多
One of the greatest unmet needs in the treatment of Parkinson’s disease（PD）is a disease-modifying therapy,which can halt the ongoing degeneration of dopaminergic neurons that is characteristic of this disorder.Curr...One of the greatest unmet needs in the treatment of Parkinson’s disease（PD）is a disease-modifying therapy,which can halt the ongoing degeneration of dopaminergic neurons that is characteristic of this disorder.Current therapies focus on managing symptoms,rather than on addressing their cause.Promising candidates for disease-modifying therapies are the dopaminergic neurotrophic factors（NTFs）.展开更多
Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with ne...Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide（NO）, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha（HIF-1α）, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione（GSNO） and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.展开更多
The prognosis of hepatocellular carcinoma(HCC) depends on tumor extension as well as hepatic function.Hepatic functional reserve is recognized as a factor affecting survival in the treatment of HCC;the ChildPugh class...The prognosis of hepatocellular carcinoma(HCC) depends on tumor extension as well as hepatic function.Hepatic functional reserve is recognized as a factor affecting survival in the treatment of HCC;the ChildPugh classif ication system is the most extensively used method for assessing hepatic functional reserve in patients with chronic liver disease,using serum albumin level to achieve accurate assessment of the status of protein metabolism.However,insuff icient attention has been given to the status of amino acid(AA) metabolism in chronic liver disease and HCC.Fischer's ratio is the molar ratio of branched-chain AAs(BCAAs:leucine,valine,isoleucine) to aromatic AAs(phenylalanine,tyrosine) and is important for assessing liver metabolism,hepatic functional reserve and the severity of liver dysfunction.Although this ratio is diff icult to determine in clinical situations,BCAAs/tyrosine molar concentration ratio(BTR) has been proposed as a simpler substitute.BTR correlates with various liver function examinations,including markers of hepatic f ibrosis,hepatic blood flow and hepatocyte function,and can thus be considered as reflecting the degree of hepatic impairment.This manuscript examines the literature to clarify whether BTR can serve as a prognostic factor for treatment of HCC.展开更多
[ Objective] This study ~med to investigate the influence of high temperature on the expression of heat shock transcription factor AtHsfAla in different genotypes of Arabidopsis. [ Method ] Arabidopsis plants overexpr...[ Objective] This study ~med to investigate the influence of high temperature on the expression of heat shock transcription factor AtHsfAla in different genotypes of Arabidopsis. [ Method ] Arabidopsis plants overexpressing heat shock transcription factor AtHsfA1 a were used as experimental materials and treated un- der high temperature at 39℃ for 1 rain and 5 min; total RNA of AtI-IsfAla was extracted, and the reverse transcription and amplification were conducted using RT- PCR technology, the amplification products were detected by electrophoresis. [ Result ] The expression levels of AtHsfA1 a in Arabidopsis plants overexpressing heat shock transcription factor AtHsfAla at high temperature and room temperature were higher than wild-type Arabidopsis; the expression levels of AtHsfAla in both wild-type Arab/dops/s and transgenic Arabidopsls plants overexpressing heat shock transcription factor AtHsfAla at high temperature of 39 ~C were higher than that at room temperature of 25 ~C, but the expression levels of AtHsfAla in wild-type Arab/dops/s and transgenic Arab/dops/s plants overexpressing heat shock transcription factor AtHsfAla varied little after high temperature treatment at 39 ~C for 1 rain or 5 rain. [ Conclusion] The expression of AtHsfAla is induced rapidly by high tem- perature, thus regulating the expression of early adversity-resistant genes. This study will lay the foundation demonstrating the mechanism of Arabidopsis heat shock transcription factor AtHsfAla.展开更多
Hypercoagulability observed in patients with inflammatory bowel diseases (IBD) may lead to thromboembolic events (TE), which affect the venous and arterial systems alike and are an important factor in patients�...Hypercoagulability observed in patients with inflammatory bowel diseases (IBD) may lead to thromboembolic events (TE), which affect the venous and arterial systems alike and are an important factor in patients’ morbidity and mortality. The risk of TE in IBD patients has been demonstrated to be approximately three-fold higher as compared to the general population. The pathogenesis of thrombosis in IBD patients is multifactorial and not fully explained. The most commonly listed factors include genetic and immune abnormalities, disequilibrium between procoagulant and anticoagulant factors, although recently, the role of endothelial damage as an IBD-triggering factor is underlined. Several studies report that the levels of some coagulation enzymes, including fibrinogen, factors V, VII, VIII, active factor XI, tissue factor, prothrombin fragment 1 + 2 and the thrombin-antithrombin complex, are altered in IBD patients. It has been demonstrated that there is a significant decrease of tissue plasminogen activator level, a marked increase of plasminogen activator inhibitor type 1 and thrombin-activable fibrinolysis inhibitor, a significantly lower level of antithrombin III and tissue factor pathway inhibitor. IBD patients have been also observed to produce an increased amount of various anticoagulant antibodies. Hyperhomocysteinemia, which is a potential risk factor for TE was also observed in some IBD patients. Further studies are necessary to assess the role of coagulation abnormalities in IBD etiology and to determine indications for thromboprophylactic treatment in patients at high risk of developing TE.展开更多
In engineering practice, tubular X-joints have been widely used in offshore structures. The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress. In this study, the stre...In engineering practice, tubular X-joints have been widely used in offshore structures. The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress. In this study, the stress concentration factor distribution along the weld toe in the hot spot stress region for tubular X-joints subject to axial loads have been analyzed by use of finite element method. Through numerical analysis, it has been found that the peak stress concentration factor is located at the saddle position. Thereafter, 80 models have been analyzed, and the effect of the geometric parameters of a tubular X-joint on the stress concentration factor has been investigated. Based on the experimental values of the numerical stress concentration factor, a parametric equation to calculate the stress concentration factor of tubular X-joints has been proposed. The accuracy of this equation has been verified against the requirement of the Fatigue Guidance Review Panel, and the proposed equation is found capable of producing reasonably accurate stress concentration factor values for tubular X-joints subject to axial loads.展开更多
Parkinson＇s disease （PD） is a neurodegenerative disease with a long preclinical phase. The continuous loss of dopaminergic （DA） neurons is one of the pathogenic hallmarks of PD. Diagnosis largely depends on clini...Parkinson＇s disease （PD） is a neurodegenerative disease with a long preclinical phase. The continuous loss of dopaminergic （DA） neurons is one of the pathogenic hallmarks of PD. Diagnosis largely depends on clinical observation, but motor dysfunctions do not emerge until 70%-80% of the nigrostriatal nerve terminals have been destroyed. Therefore, a biomarker that indicates the degeneration of DA neurons is urgently needed. Transcrip- tion factors are sequence-specific DNA-binding proteins that regulate RNA synthesis from a DNA template. The precise control of gene expression plays a critical role in the development, maintenance, and survival of cells, including DA neurons. Deficiency of certain transcription factors has been associated with DA neuron loss and PD. In this review, we focus on some transcription factors and discuss their structure, function, mechanisms of neuropro- tection, and their potential for use as biomarkers indicating the degeneration of DA neurons.展开更多
The photodegradation of bisphenol S （BPS） in aqueous solutions was studied under different conditions. Photolysis and kinetics were investigated, as were the photolysis mechanism and the influences of initial pH val...The photodegradation of bisphenol S （BPS） in aqueous solutions was studied under different conditions. Photolysis and kinetics were investigated, as were the photolysis mechanism and the influences of initial pH value, light source, and environmental substances in water. The results showed that the photolysis of BPS occurred under UV light, and the rate increased with light source intensity. The photolysis of 5.0-50.0 mg/L BPS in water followed first-order kinetics： the rate was γ = 0.0161CBPS under a 40-W UV-lamp, and the degradation half-life was 43.1 min. Due to its absorption of light, direct photolysis of BPS was a predominant pathway for BPS but was not obviously affected by reactive oxygen species. The results confirmed that the photolysis rates of BPS in alkaline water solution were faster than those in acidic and neutral water solution because of the ionization of BPS. The photodegradation rate of BPS increased in the presence of chloride and ferric ions, while the rate was inhibited by nitrate and phosphate in aqueous solution.展开更多
AIM:To compare the clinicopathological characteristics of human epidermal growth factor receptor 2 (HER2)-positive and HER2-negative Barrett's adenocarcinoma in Japan. METHODS:We performed immunohistochemical anal...AIM:To compare the clinicopathological characteristics of human epidermal growth factor receptor 2 (HER2)-positive and HER2-negative Barrett's adenocarcinoma in Japan. METHODS:We performed immunohistochemical analysis of HER2 in 30 samples taken from patients with Barrett's adenocarcinoma and dual color in situ hybridization in cases showing 2+ reactions. We compared the clinicopathological characteristics of HER2-positive and HER2-negative patients.RESULTS:HER2 positivity was identified in 8 (27%) carcinoma samples. We found that HER2 expression was associated with p53 overexpression (100% vs 52.6% in pT1 tumor; 100% vs 54.5% in all stage tumor, P < 0.05) and protruding lesions at the early disease stage. There was no association between the mucin phenotype of the carcinomas and prognosis. HER2 expression and low clinical stage were unexpectedly different between Barrett's adenocarcinoma patients and gastric cancer patients, but the macroscopic features may be associated with earlier diagnosis in these patients. CONCLUSION:Our results suggest that HER2-positive Barrett's adenocarcinomas are associated with p53 overexpression and lesion protrusion at the early disease stage.展开更多
Model simulation and scenario change analysis are the core contents of the future land-use change（LUC） study. In this paper, land use status data of the Three Gorges Reservoir Region（TGRR） in 1990 was used as base...Model simulation and scenario change analysis are the core contents of the future land-use change（LUC） study. In this paper, land use status data of the Three Gorges Reservoir Region（TGRR） in 1990 was used as base data. The relationship between driving factors and land-use change was analyzed by using binary logistic stepwise regression analysis, based on which land use in 2010 was simulated by CLUE-S model. After the inspection and determination of main parameters impacting on driving factors of land use in the TGRR, land use of this region in 2030 was simulated based on four scenarios, including natural growth, food security, migration-related construction and ecological conservation. The results were shown as follows：（1） The areas under ROC curves of land-use types（LUTs） were both greater than 0.8 under the analysis and inspection of binary logistic model. These LUTs include paddy field, dryland, woodland, grassland, construction land and water area. Therefore, it has a strong interpretation ability of driving factors on land use, which can be used in the estimation of land use probability distribution.（2） The Kappa coefficients, verified from the result of land-use simulation in 2010, were shown of paddy field 0.9, dryland 0.95, woodland 0.97, grassland 0.84, construction land 0.85 and water area 0.77. So the results of simulation could meet the needs of future simulation and prediction.（3） The results of multi-scenario simulation showed a spatial competitive relationship between different LUTs, and an influence on food security, migration-related construction and ecological conservation in the TGRR, including some land use actions such as the large-scale conversion from paddy field to dryland, the occupation on cultivated land, woodland and grassland for rapid expansion of construction land, the reclamation of woodland and grassland into cultivated land, returning steep sloping farmland back into woodland and grassland. Therefore, it is necessary to balance the needs of various aspects in land use optimization, to achieve the coordination between socio-economy and ecological environment.展开更多
The attenuation factor or quality factor(Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a m...The attenuation factor or quality factor(Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a method to calculate the Q-factor based on the prestack Q-factor inversion and the generalized S-transform. The proposed method specifies a standard primary wavelet and calculates the cumulative Q-factors; then, it finds the interlaminar Q-factors using the relation between Q and offset(QVO) and the Dix formula. The proposed method is alternative to methods that calculate interlaminar Q-factors after horizon picking. Because the frequency spectrum of each horizon can be extracted continuously on a 2D time–frequency spectrum, the method is called the continuous spectral ratio slope(CSRS) method. Compared with the other Q-inversion methods, the method offers nearly effortless computations and stability, and has mathematical and physical significance. We use numerical modeling to verify the feasibility of the method and apply it to real data from an oilfield in Ahdeb, Iraq. The results suggest that the resolution and spatial stability of the Q-profile are optimal and contain abundant interlaminar information that is extremely helpful in making lithology and fluid predictions.展开更多
Huntington’s disease（HD）is an autosomal dominant,monogenic,progressive,neurodegenerative and rare disease with a frequency of10 per 100,000 in the Caucasian population and occurring more rarely in other races（Squi...Huntington’s disease（HD）is an autosomal dominant,monogenic,progressive,neurodegenerative and rare disease with a frequency of10 per 100,000 in the Caucasian population and occurring more rarely in other races（Squitieri et al.,1994）.HD is,nevertheless,one of the most frequently and extensively studied diseases of those caused by a dynamic mutation.The HD mutation is located on the short arm of the 4th chromosome within the HTT gene.展开更多
研究了单个线性关系是可闭线性关系的充分必要条件;并对L0=(A B C D),其中A,B,C,D是相应Hilbert空间上的线性关系,利用C相对A的有界性与B相对D的有界性及A,D的可闭性,推出了L_(0)也是可闭线性关系;同时,对于有界线性算子S=(S_(1) S_(2) ...研究了单个线性关系是可闭线性关系的充分必要条件;并对L0=(A B C D),其中A,B,C,D是相应Hilbert空间上的线性关系,利用C相对A的有界性与B相对D的有界性及A,D的可闭性,推出了L_(0)也是可闭线性关系;同时,对于有界线性算子S=(S_(1) S_(2) S_(3) S_(4)),得到当满足一定条件时L_(0)-μS的Frobenius-Schur分解公式,并得到了当L_(0)可闭时L_(0)的表达式,最后研究了L_(0)的S-本质谱。展开更多
A component （s-factor） with obvious promoting effect on hydrogen evolution of hydrogenase has beenisolated and extracted from a Cell=free preparation of Spirulina platensis.The effect of the s-factor in the re-actio...A component （s-factor） with obvious promoting effect on hydrogen evolution of hydrogenase has beenisolated and extracted from a Cell=free preparation of Spirulina platensis.The effect of the s-factor in the re-action system is similar to that of Na<sub>2</sub>S<sub>2</sub>O<sub>4</sub>, but is coupled with ligh. The s-factor has the maximumabsorption peak at 620 nm in the oxidized state, at 590 nm in the reduced state. The partially purifieds-factor showed two bands by SDS-PAGE and is distinctly different from phycocyanin,which has nochange of oxidized state and reduced state absorption spectra, and also has no promoting effect onhydrogenase of Spirulina platensis under the light.展开更多
文摘The current various proposals at the International Maritime Organisation （IMO） for the s factor （probability of surviving a given flooding） make no reference to survival time. The paper shows a direct link of the ＂prime＂ s factor with the time to capsize and shows how to utilise experimental data from 30-minute test runs for the s factor based on longer duration of tests. Unexpectedly, the extension of tests has a modest effect on the survival factor, and hence-modest effect on subdivision index A. Much more important is improving a deficient formulation for the required index R, as flooding cases with si = 1 have an infinite survival time.
基金supported by the National Natural Science Foundation of China(81070926 and 81571281)
文摘Chronic cerebrovascular hypoperfusion is a high-risk factor for Alzheimer＇s disease（AD） as it is conducive to beta amyloid（Ab） over-production. Brainderived neurotrophic factor（BDNF） is a member of the neurotrophin family widely expressed in the central nervous system. The structure of the rat BDNF gene is complex, consisting of eight non-coding exons（I–VIII） and one coding exon（IX）. The BDNF gene is transcribed from multiple promoters located upstream of different 50 noncoding exons to produce a heterogeneous population of BDNF m RNAs. S-adenosylmethionine（SAM） produced in the methionine cycle is the primary methyl donor and the precursor of glutathione. In this study, a cerebrovascular hypoperfusion rat model and an Ab intrahippocampal injection rat model were used to explore the expression profiles of all BDNF transcripts in the hippocampus with chronic cerebrovascular hypoperfusion or Ab injection as well as with SAM treatment. We found that the BDNF m RNAs and protein were down-regulated in the hippocampus undergoing chronic cerebrovascular hypoperfusion as well as Ab treatment, and BDNF exons IV and VI played key roles. SAM improved the low BDNF expression following these insults mainly through exons IV and VI.These results suggest that SAM plays a neuroprotective role by increasing the expression of endogenous BDNF and could be a potential target for AD therapy.
基金supported by the National Key R&D Program of China(Nos.2022YFC3700400 and 2022YFC3704000).
文摘The large dynamic range and high performance of temperature and humidity profile lidar made it a popular tool for monitoring the atmospheric environment.In this study,we carried out an accurate analysis of the key components of the lidar system,including lasers,the emitting and receiving light paths,and photodetectors.We combined the validation of simulations with experimental testing,and then the applicability indicators and necessary conditions in accordance were suggested.For the frequency stability of the laser,when the wavelength shift is less than 0.15%,the measurement accuracy of the system can be guaranteed to be less than 5%.The degree of near-field signal distortion will be significantly impacted by the size of the geometric factor’s transition zone.The introduced measurement error is less than 2%when the deviation angle of the emission axis is less than 0.1 mrad.It has been tested that selecting a low-sensitivity detector can help to improve the sensitivity of temperature detection since this channel is sensitive to the detector’s nonlinearity.To enhance lidar’s detection capabilities and direct the lidar system design process,it is beneficial to analyze the precision of the key components.
文摘One of the greatest unmet needs in the treatment of Parkinson’s disease（PD）is a disease-modifying therapy,which can halt the ongoing degeneration of dopaminergic neurons that is characteristic of this disorder.Current therapies focus on managing symptoms,rather than on addressing their cause.Promising candidates for disease-modifying therapies are the dopaminergic neurotrophic factors（NTFs）.
基金supported by grants from VA merit awards(BX3401 and RX2090)
文摘Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide（NO）, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha（HIF-1α）, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione（GSNO） and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.
文摘The prognosis of hepatocellular carcinoma(HCC) depends on tumor extension as well as hepatic function.Hepatic functional reserve is recognized as a factor affecting survival in the treatment of HCC;the ChildPugh classif ication system is the most extensively used method for assessing hepatic functional reserve in patients with chronic liver disease,using serum albumin level to achieve accurate assessment of the status of protein metabolism.However,insuff icient attention has been given to the status of amino acid(AA) metabolism in chronic liver disease and HCC.Fischer's ratio is the molar ratio of branched-chain AAs(BCAAs:leucine,valine,isoleucine) to aromatic AAs(phenylalanine,tyrosine) and is important for assessing liver metabolism,hepatic functional reserve and the severity of liver dysfunction.Although this ratio is diff icult to determine in clinical situations,BCAAs/tyrosine molar concentration ratio(BTR) has been proposed as a simpler substitute.BTR correlates with various liver function examinations,including markers of hepatic f ibrosis,hepatic blood flow and hepatocyte function,and can thus be considered as reflecting the degree of hepatic impairment.This manuscript examines the literature to clarify whether BTR can serve as a prognostic factor for treatment of HCC.
基金Supported by National Natural Science Foundation of China(31060039,31260061)Natural Science Foundation of Yunnan Province(2010ZC163)+1 种基金College-level Project of Kunming University(YJL11025)College-level Project for Key Discipline Construction of Kunming University
文摘[ Objective] This study ~med to investigate the influence of high temperature on the expression of heat shock transcription factor AtHsfAla in different genotypes of Arabidopsis. [ Method ] Arabidopsis plants overexpressing heat shock transcription factor AtHsfA1 a were used as experimental materials and treated un- der high temperature at 39℃ for 1 rain and 5 min; total RNA of AtI-IsfAla was extracted, and the reverse transcription and amplification were conducted using RT- PCR technology, the amplification products were detected by electrophoresis. [ Result ] The expression levels of AtHsfA1 a in Arabidopsis plants overexpressing heat shock transcription factor AtHsfAla at high temperature and room temperature were higher than wild-type Arabidopsis; the expression levels of AtHsfAla in both wild-type Arab/dops/s and transgenic Arabidopsls plants overexpressing heat shock transcription factor AtHsfAla at high temperature of 39 ~C were higher than that at room temperature of 25 ~C, but the expression levels of AtHsfAla in wild-type Arab/dops/s and transgenic Arab/dops/s plants overexpressing heat shock transcription factor AtHsfAla varied little after high temperature treatment at 39 ~C for 1 rain or 5 rain. [ Conclusion] The expression of AtHsfAla is induced rapidly by high tem- perature, thus regulating the expression of early adversity-resistant genes. This study will lay the foundation demonstrating the mechanism of Arabidopsis heat shock transcription factor AtHsfAla.
文摘Hypercoagulability observed in patients with inflammatory bowel diseases (IBD) may lead to thromboembolic events (TE), which affect the venous and arterial systems alike and are an important factor in patients’ morbidity and mortality. The risk of TE in IBD patients has been demonstrated to be approximately three-fold higher as compared to the general population. The pathogenesis of thrombosis in IBD patients is multifactorial and not fully explained. The most commonly listed factors include genetic and immune abnormalities, disequilibrium between procoagulant and anticoagulant factors, although recently, the role of endothelial damage as an IBD-triggering factor is underlined. Several studies report that the levels of some coagulation enzymes, including fibrinogen, factors V, VII, VIII, active factor XI, tissue factor, prothrombin fragment 1 + 2 and the thrombin-antithrombin complex, are altered in IBD patients. It has been demonstrated that there is a significant decrease of tissue plasminogen activator level, a marked increase of plasminogen activator inhibitor type 1 and thrombin-activable fibrinolysis inhibitor, a significantly lower level of antithrombin III and tissue factor pathway inhibitor. IBD patients have been also observed to produce an increased amount of various anticoagulant antibodies. Hyperhomocysteinemia, which is a potential risk factor for TE was also observed in some IBD patients. Further studies are necessary to assess the role of coagulation abnormalities in IBD etiology and to determine indications for thromboprophylactic treatment in patients at high risk of developing TE.
基金The research work was financially supported by the National Natural Scientice Foundation of China(Grant No.10142001)by the Shandong Provincial Natural Scientice Foundation(Grant No.Y2006F46)
文摘In engineering practice, tubular X-joints have been widely used in offshore structures. The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress. In this study, the stress concentration factor distribution along the weld toe in the hot spot stress region for tubular X-joints subject to axial loads have been analyzed by use of finite element method. Through numerical analysis, it has been found that the peak stress concentration factor is located at the saddle position. Thereafter, 80 models have been analyzed, and the effect of the geometric parameters of a tubular X-joint on the stress concentration factor has been investigated. Based on the experimental values of the numerical stress concentration factor, a parametric equation to calculate the stress concentration factor of tubular X-joints has been proposed. The accuracy of this equation has been verified against the requirement of the Fatigue Guidance Review Panel, and the proposed equation is found capable of producing reasonably accurate stress concentration factor values for tubular X-joints subject to axial loads.
基金supported by the National Key Research and Development Program of China (2016YFC1306603)the National Natural Science Foundation of China (31671060)
文摘Parkinson＇s disease （PD） is a neurodegenerative disease with a long preclinical phase. The continuous loss of dopaminergic （DA） neurons is one of the pathogenic hallmarks of PD. Diagnosis largely depends on clinical observation, but motor dysfunctions do not emerge until 70%-80% of the nigrostriatal nerve terminals have been destroyed. Therefore, a biomarker that indicates the degeneration of DA neurons is urgently needed. Transcrip- tion factors are sequence-specific DNA-binding proteins that regulate RNA synthesis from a DNA template. The precise control of gene expression plays a critical role in the development, maintenance, and survival of cells, including DA neurons. Deficiency of certain transcription factors has been associated with DA neuron loss and PD. In this review, we focus on some transcription factors and discuss their structure, function, mechanisms of neuropro- tection, and their potential for use as biomarkers indicating the degeneration of DA neurons.
基金supported by the Major Projects of National Science and Technology on Water Pollution Control and Treatment (No. 2008ZX07101-003)the Natural Sciences Research Project of Changzhou Institute of Technology (No. YN1009)
文摘The photodegradation of bisphenol S （BPS） in aqueous solutions was studied under different conditions. Photolysis and kinetics were investigated, as were the photolysis mechanism and the influences of initial pH value, light source, and environmental substances in water. The results showed that the photolysis of BPS occurred under UV light, and the rate increased with light source intensity. The photolysis of 5.0-50.0 mg/L BPS in water followed first-order kinetics： the rate was γ = 0.0161CBPS under a 40-W UV-lamp, and the degradation half-life was 43.1 min. Due to its absorption of light, direct photolysis of BPS was a predominant pathway for BPS but was not obviously affected by reactive oxygen species. The results confirmed that the photolysis rates of BPS in alkaline water solution were faster than those in acidic and neutral water solution because of the ionization of BPS. The photodegradation rate of BPS increased in the presence of chloride and ferric ions, while the rate was inhibited by nitrate and phosphate in aqueous solution.
文摘AIM:To compare the clinicopathological characteristics of human epidermal growth factor receptor 2 (HER2)-positive and HER2-negative Barrett's adenocarcinoma in Japan. METHODS:We performed immunohistochemical analysis of HER2 in 30 samples taken from patients with Barrett's adenocarcinoma and dual color in situ hybridization in cases showing 2+ reactions. We compared the clinicopathological characteristics of HER2-positive and HER2-negative patients.RESULTS:HER2 positivity was identified in 8 (27%) carcinoma samples. We found that HER2 expression was associated with p53 overexpression (100% vs 52.6% in pT1 tumor; 100% vs 54.5% in all stage tumor, P < 0.05) and protruding lesions at the early disease stage. There was no association between the mucin phenotype of the carcinomas and prognosis. HER2 expression and low clinical stage were unexpectedly different between Barrett's adenocarcinoma patients and gastric cancer patients, but the macroscopic features may be associated with earlier diagnosis in these patients. CONCLUSION:Our results suggest that HER2-positive Barrett's adenocarcinomas are associated with p53 overexpression and lesion protrusion at the early disease stage.
基金Chongqing University Innovation Team for 2016,No.CXTDX201601017Chongqing Research Program of Basic Research and Frontier Technology,No.cstc2017jcyjB0317
文摘Model simulation and scenario change analysis are the core contents of the future land-use change（LUC） study. In this paper, land use status data of the Three Gorges Reservoir Region（TGRR） in 1990 was used as base data. The relationship between driving factors and land-use change was analyzed by using binary logistic stepwise regression analysis, based on which land use in 2010 was simulated by CLUE-S model. After the inspection and determination of main parameters impacting on driving factors of land use in the TGRR, land use of this region in 2030 was simulated based on four scenarios, including natural growth, food security, migration-related construction and ecological conservation. The results were shown as follows：（1） The areas under ROC curves of land-use types（LUTs） were both greater than 0.8 under the analysis and inspection of binary logistic model. These LUTs include paddy field, dryland, woodland, grassland, construction land and water area. Therefore, it has a strong interpretation ability of driving factors on land use, which can be used in the estimation of land use probability distribution.（2） The Kappa coefficients, verified from the result of land-use simulation in 2010, were shown of paddy field 0.9, dryland 0.95, woodland 0.97, grassland 0.84, construction land 0.85 and water area 0.77. So the results of simulation could meet the needs of future simulation and prediction.（3） The results of multi-scenario simulation showed a spatial competitive relationship between different LUTs, and an influence on food security, migration-related construction and ecological conservation in the TGRR, including some land use actions such as the large-scale conversion from paddy field to dryland, the occupation on cultivated land, woodland and grassland for rapid expansion of construction land, the reclamation of woodland and grassland into cultivated land, returning steep sloping farmland back into woodland and grassland. Therefore, it is necessary to balance the needs of various aspects in land use optimization, to achieve the coordination between socio-economy and ecological environment.
基金supported by The National Key Research and Development Program Plane(No.2017YFC0601505)National Natural Science Foundation(No.41672325)Science&Technology Department of Sichuan Province Technology Project(No.2017GZ0393)
文摘The attenuation factor or quality factor(Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a method to calculate the Q-factor based on the prestack Q-factor inversion and the generalized S-transform. The proposed method specifies a standard primary wavelet and calculates the cumulative Q-factors; then, it finds the interlaminar Q-factors using the relation between Q and offset(QVO) and the Dix formula. The proposed method is alternative to methods that calculate interlaminar Q-factors after horizon picking. Because the frequency spectrum of each horizon can be extracted continuously on a 2D time–frequency spectrum, the method is called the continuous spectral ratio slope(CSRS) method. Compared with the other Q-inversion methods, the method offers nearly effortless computations and stability, and has mathematical and physical significance. We use numerical modeling to verify the feasibility of the method and apply it to real data from an oilfield in Ahdeb, Iraq. The results suggest that the resolution and spatial stability of the Q-profile are optimal and contain abundant interlaminar information that is extremely helpful in making lithology and fluid predictions.
文摘Huntington’s disease（HD）is an autosomal dominant,monogenic,progressive,neurodegenerative and rare disease with a frequency of10 per 100,000 in the Caucasian population and occurring more rarely in other races（Squitieri et al.,1994）.HD is,nevertheless,one of the most frequently and extensively studied diseases of those caused by a dynamic mutation.The HD mutation is located on the short arm of the 4th chromosome within the HTT gene.
文摘研究了单个线性关系是可闭线性关系的充分必要条件;并对L0=(A B C D),其中A,B,C,D是相应Hilbert空间上的线性关系,利用C相对A的有界性与B相对D的有界性及A,D的可闭性,推出了L_(0)也是可闭线性关系;同时,对于有界线性算子S=(S_(1) S_(2) S_(3) S_(4)),得到当满足一定条件时L_(0)-μS的Frobenius-Schur分解公式,并得到了当L_(0)可闭时L_(0)的表达式,最后研究了L_(0)的S-本质谱。
文摘A component （s-factor） with obvious promoting effect on hydrogen evolution of hydrogenase has beenisolated and extracted from a Cell=free preparation of Spirulina platensis.The effect of the s-factor in the re-action system is similar to that of Na<sub>2</sub>S<sub>2</sub>O<sub>4</sub>, but is coupled with ligh. The s-factor has the maximumabsorption peak at 620 nm in the oxidized state, at 590 nm in the reduced state. The partially purifieds-factor showed two bands by SDS-PAGE and is distinctly different from phycocyanin,which has nochange of oxidized state and reduced state absorption spectra, and also has no promoting effect onhydrogenase of Spirulina platensis under the light.
